Injection control system



July 20, 1948. H. s. ROBINSON 2,445,337

mmcnou comnoz. srs'rsn Filed Aug. 9, 1945 FROM SOURCE OF FROM ENGINE OIL WATER SUPPLY PRESSURE LINE Hugh Robinson WLWM Patented July 20, 1948 UNITED STATES PATENT OFFICE INJECTION CONTROL SYSTEM Hugh S. Robinson, United States Navy Application August 9, 1945, Serial No. 809,903

Claims. (Cl. 123-25) (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) The present invention relates to new and useful improvements in attachments for internal combustion engines, and more particularly to improvements in a fluidinjection control system for internal combustion engines.

The invention is generally concerned with the injection of a fluid, such as water, into the fuel mixture supplied by the carburetor to the combustion chambers of internal combustion engines. Such water injection operates as a coolant and anti-detonator to reduce knocking, particularly when the engine is under load. 7

An object of the present invention is to provide a compact and reliable device for selectively controlling the admission of anti-detonating fluid to an internal combustion engine.

Another object of the invention is to provide a mechanism in the form of a valve assembly for selectively metering water to the internal combustion engine according to the manifold pressure.

A further object of the invention is to provide a mechanism of the above type which operates to positively and automatically shut off the metered water supply' upon, stopping of the engine.

The invention still further aims to provide a mechanism of the abovetype which includes a metering valve operated in response to variations in pressures occasioned during operation .of the engine and upon stopping thereof.

The above and other objects of the invention will in part be obvious and will be hereinafter more fully pointed out.

- In the accompanying drawing the figure is seetional view taken longitudinally through the housing of the metering device and showing the same diagrammatically. positioned with respect to the fuel mixture conduit.

Referring more indetail to the accompanying drawing, the device is. illustrated as enclosed within a casing or housing which includes a central body portion I0 and end closure members ll, ila which are secured to the body portion ill by bolts l2, or the like, passing through annular spacer elements I3, I311. The end closure members ll, Ila are each provided with outward extensions I4, Ma affording internal recesses facing countersunk recesses in the adjacent ends of the body portion to provide internal end cavities in the housing which are divided by flexible transverse diaphragms I5, I So into pairs of chambers i6, Na, and i1, Ila, respectively. The edges of the diaphragms are secured between the spacer elements and the adjacent faces of the body portion I0.

The central portions of the diaphragms I5, I51; are secured to supporting cup members II, "a, respectively, which also serve as seats for the inner ends of coil springs I9, 20,. respectively.

The opposite end of the spring I9 within the chamber i6 is centered on a flange 2| at the inner end of a bolt 22 which extends through the end adjustably mounted in the end of the closure extension Ma. The inner end of the bolt 24 is longitudinally bored, as at 25, to receive the end of a stem 26 which is secured to a spindle 21 on the opposite side of the diaphragm lia which is clamped thereby between the surface of th cup member I8a and a plate 28.

The body portion in is provided with a centra-lly disposed valve chamber 29 into which the spindle 21 extends from the chamber H. The chamber I1 is adapted to be connected through the passage 30 in the body portion with a source of fluid under pressure when the engine is operating, such as the fuel, oil or water system thereof. A ring seal 3! is carried by the body portion and cooperates with the spindle 21 to prevent leakage of fluid between the chambers l1 and 29. A valve stem 32 is scecured to the cup member I8 and serves to clamp the central portion of the diaphragm l5 between the cup member and a plate 33. The valve stem extends through an axially bored boss 34 extending into the chamber lia which is adapted to be connected through passage 35 with a source of anti-detonating fluid,,such as a water supply tank (not shown). The chamber lid is in communication with a collecting recess 36 through passages 31. The'valve stem carries a valve member 38 at the inner end thereof and this valve member is provided with a tapered metering surface cooperating with the surface of a passage 38 whichprovides communication between the recess 36 and the chamberfitl A' passage 40 in the body portion ill affords communication between the chamber 29 and a conduit 4| which opens centrally into the throttle tube which may be the fuel mixture or air conduit 42 leading to and under the suction of the engine manifold (not shown). The passage of air and/or fuel is controlled by a conventional throttle valve 43 in the tube 42. The closed chamber I8 is in communication with the conduit 42 through a. suitable form of conduit 44 so that the chamber I6 is thus under the influence of the manifold pressure, or rather suction, as is the chamber 29. The

water may be admitted at any point between the carburetor and the valves.

In operation, when the engine is stopped with no pressure in the chamber II, the relative forces of the springs I9, are so adjusted that the spring 20 will force the diaphragm Ilia inwardly and'with it the spindle 21 until the rubber pad 45 at the inner end of the spindle will seat against the adjacent surface of the chamber 29 with the valve member 38 closed so as to provide a positive seal against flow of water through the passage 39. During this positioning of the parts the spring 20 will overcome the force of the spring It so as to maintain the valve member seated. Upon starting of the engine. the chamber l'la being vented to the. atmosphere through a hole 46 in the closure member Ila, the pressure of the fuel. oil or water system which is connected to the passage 30, will force the diaphragm lia outwardly and with it the spindle 21 so as to permit the spring-lt'to tend to force the valve member 38 away from the valve seating surface 38 to admit water from the chamber lid to the chamber 28. When the engine is idling and not under load, the throttle valve 43 will be toward a closed position and the suction in the manifold and in the conduit 42 will be relatively high and this suction or relatively low pressure will be transmitted to the chamber It through the conduit 44 so that the diaphragm it will be urged outwardly of the body portion against the action of the spring is, thus tending to close the metering valve to reduce or stop the passage of water, into the fuel conduit, depending on the manifold suction. As the throttle valve is opened under increasing engine load, the manifold suction will be reduced (or, conversely the manifold pressure will increase) and the same change will occur in chamber l6 so that resistance to'movement of the valve member 38 under influence of the spring l9 will decrease and the valve member will be shifted toward open position. This will progressively admit more water to the chamber 29 and to the conduit 4i so that the water will be injected into the fuel mixture in the conduit 42.

Thus, the admission of water to the explosion chambers is increasingly metered as, the suction decreases, or conversely as theabsolute manifold pressure increases. The setting of the springs I9, 20 may be varied for any pressure valves required for the selected operating conditions of the metering valve. Under normal operating conditions, the valve is under positive spring pressure tending to open the same and under variable manifold suction tending to close the same by counteracting the force of the spring l9. Thus, the valve is under the influence of the resultant differential beunder the aforesaid forces so that the valve member is urged by the spindle 21 toward a closed position with the pad 45 ultimately seating around the passage 39 to provide apositive seal which willprevent additional water being drawn into the engine after stopping or stalling thereof.

It will be seen from the foregoing description in connection witlfthe drawing that a highly efhcient and relatively simple metering valve assembly is provided for selectively vcontrolling the admission of water, as an anti-detonator. to the explosion chambers of an internal combustion engine is hereby provided. However, although one .form of the invention has been shown for purposes or illustration, it is to be clearly understood that various changes in the details of construction, arrangement of parts and mode of operation may be accomplished without departing from the scope of the invention as set forth in the appended claims. a

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

' I claim: v

1. In a fluid injection system for internal combustion engines having a throttle tube subject to manifold pressure, the provision of a housing having fluid conduit means therethrough connected to the throttle tube, a metering valve in said conduit means for controlling the passage of the fluid to the throttle tube in amounts inversely proportional to the manifold pressure, means providing a chamber in said housing subject to pressure created by revolution of the engine, a valve closing member normally held in inoperative position by the pressure within said chamber, and spring means for shifting said closing member when the pressure in said chamber drops below a predetermined point whereby to positively close said valve.

2. A device for selectively controlling the admission of water to the fuel mixture of an internal combustion engine in response to the manifold pressure thereof, comprising a housing having conduit means providing communication between the engine and the source of supply of the water to be added, metering valve means in said housing for controlling the passage of water through said conduit means in response to manifold pressure. and means for positively closing said metering valve upon stopping of the engine or upon reduction of the engine revolutions per minute below a pre-set minimum.

3. A device for selectively controlling the admission of water'to the fuel mixture of an internal combustion engine in response to the manifold pressure thereof, comprising a housing provided with a cavity and a diaphragm dividing said cavity into a pair of chambers, one of said chambers being subject to manifold pressure and having spring means therein acting on said diaphragm and opposing said manifold pressure, the othervof said chambers being in communication with the source of supply of the water to be admitted and with the engine, valve means connected to said diaphragm and operated thereby for controlling the admission of water to the engine according to the differential force exerted on said diaphragm by said spring means and the manifold pressure, and means operable upon stopping of the engine for positively closing said valve means.

4. A device for selectively controlling the admission of water to the fuel mixture of an internal combustion engine in response to the manifold pressure thereof, comprising a housing provided with a cavity and a diaphragm dividing said cavity into a pair of chambers, one of said chambers being subject to manifold pressure and having spring means therein acting on said diaphragm and opposing said manifold pressure, the

other of said chambers being in communication with the source of supply of the water to be admitted and with the engine, valve means connected to said diaphragm and operated thereby for controlling the admission of water to the engine according to the differential force exerted on said diaphragm by said spring means and the manifold pressure, and spring loaded means held in open position by the oil pressure of the engine but operable upon stopping of the engine to positlvely close said valve means.

5. A device for selectively controlling the admission of water to the fuel mixture of an internal combustion engine in response to the manifold pressure thereof, comprising a housing provided with a cavity and a diaphragm dividing said cavity into a pair of chambers, one of said chambers being subject to manifold pressure and having spring means therein acting on said diaphragm and opposing said manifold pressure, the other 01 said chambers being in communication with the source of supply of the water to be admitted and with the engine, valve means connected to said diaphragm and operated thereby for controlling the admission of water to the engine according to the "differential force exerted on said diaphragm by said spring means and the manifold pressure, an additional chamber having a flexible wall portion and in communication with the oil pressure line of the engine, a spindle car'- ried by said wall portion and normally held in retracted position by the oil pressure, and spring means for forcing said spindle into contact with said valve means to positively close the same upon stopping of the engine and resultant failure of the oil pressure.

' HUGH S. ROBINSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

